fa تخصصي Association study پژوهشي Research <div style="text-align: justify;"><span style="font-size:11pt"><span style="text-justify:kashida"><span style="text-kashida:0%"><span style="line-height:normal"><span sans-serif="" style="font-family:Calibri,"><span style="background:white"><span new="" roman="" style="font-family:" times=""><span style="color:black"><strong>Background</strong> :Autism spectrum disorder(ASD) is a complicated neurodevelopmental disease with social communication disorder, language problem and restricted repetitive patterns and restricted repetitive patterns of behavior, activities and interests. Attention deficit hyperactivity disorder (ADHD) is a pediatric psychiatric disorder with symptoms including attention deficit, hyperactivity, and impulsiveness, which can persist into adult life. <i>SHANK</i> gene family encodes Shank proteins that are multidomain scaffold proteins involved in binding of the postsynaptic density in neurotransmitter receptors, ion channels and several G-protein-coupled signaling pathways. <i>SHANK3</i>, also known as proline-rich synapse associated protein 2 (ProSAP2), is a protein encoded by the <i>SHANK3</i> gene located in human chromosome 22, play an essential role in synapse formation spine maturation and scaffold activity.<br> <strong>Objectives</strong>: In present study the expression level of <i>SHANK3</i> in ASD and ADHD patients &nbsp;was assessed.Method: &nbsp;mRNA level of the <i>SHANK3</i> were evaluated in peripheral blood of 450 unrelated ASD patients, 450 unrelated ADHD patients and the normal group included 490 unrelated non-psychiatric children by quantitative RT-PCR. In addition, gene expression and their correlation with clinical symptoms were examined.<br> <strong>Results</strong>: Showed mRNA level of <i>SHANK3</i> gene was significantly </span></span></span><span style="background:white"><span new="" roman="" style="font-family:" times="">down-regulated<span style="color:black"> in ASD patients vs. normal children. In ADHD, a significant reduction of <i>SHANK3 </i>expression was also detected comparing to normal children.<br> <strong>Conclusions</strong>: The <i>SHANK</i> family specially <i>SHANK3</i> gene may play an essential role in the etiology of ASD and ADHD. Findings also may reveal a shared genetic basis in two neurodevelopment disorders related to synaptic pathways. </span></span></span></span></span></span></span></span></div> SHANK3, ASD, ADHD, quantitative PCR. 0 0 http://humangeneticsgenomics.ir/browse.php?a_code=A-10-307-2&slc_lang=fa&sid=1 Hanieh Bai 1003194753284600330 1003194753284600330 No Department of Biology, Faculty of Biological Sciences, Islamic Azad University, North Tehran Branch, Tehran, Iran Seyed Yousef Seyedena 1003194753284600331 1003194753284600331 No Department of Biology, Faculty of Biological Sciences, Islamic Azad University, North Tehran Branch, Tehran, Iran Morteza Karimipoor 1003194753284600332 1003194753284600332 No Molecular Medicine department, Biotechnology Research Center, Pasteur Institute of Iran, Tehran, Iran Mehrdad Hashemi 1003194753284600333 1003194753284600333 Yes Department of Genetics, Faculty of Advanced Science, Islamic Azad University, Tehran, Iran